梅雨锋暴雨雨团运动场结构演变模拟分析

利用中尺度数值模式MM5对1998年7月29-30日发生于长江中下游的暴雨过程进行了模拟。对两个相邻雨团的运动场结构进行分析，揭示了梅雨锋暴雨雨团的相互作用对其运动场结构的影响。分析表明，由于新雨团的生成，原有邻近雨团上升气流结构由一种形式的不对称转为另一种形式的不对称。中尺度涡管不仅在垂直方向呈波状，在水平方向也随着雨团位置和降雨的强弱而波动。

Analysis of Evolution of Motion Field Structure of Rain Masses in Mei-yu

On the basis of the simulating results of the heavy rain occurred from July 29th to 30th, 1998 in the middle and lower reaches of the Yangtze River by means of MM5, the motion field structures of adjacent rainmasses are analyzed. The effect of the interaction of rainmasses of Meiyu front on their motion field structures is revealed. Due to the generation of new rainmass, and the anaflow structure of the adjacent one's changes from one kind of asymmetry to another type. The mesoscale vortex tube is wave-shaped not only in height, but also in the horizontal plane. Its wave shape in horizontal plane is associated with the location of rainmasses and the areas of strong and weak rainfall.